UEGCL · Meter Commissioning Review

Load Profile Analysis — LGZ16999348

Meter Serial: LGZ16999348 Recording Period: 2026-09-14 to 2026-10-05 Interval: 1-hour LP1 Prepared: 2026-10-12

§1Operating Summary (Normal Period)

Active Power Avg

0.06 MW

Range: 0.01 – 0.15 MW

Reactive Power

0.00–0.12 Mvar

Stable throughout

Voltage (L-L avg)

251.98 kV

Implies 251.98 kV L-L (~220 kV nominal)

Frequency

49.77–50.52 Hz

Within ±0.5 Hz tolerance

Total Energy

32 MWh

489 operating hours

Current Imbalance

9.16 %

L1=0.110 L2=0.101 L3=0.103 kA

§2Reactive Power Profile

Mvar vs Time (2026-09-14 – 2026-10-05)

Date	Min Mvar	Max Mvar	Avg Mvar	Day Range	Assessment
2026-09-15	0.03	0.07	0.04	0.04	✓ Stable — normal variation
2026-09-16	0.03	0.06	0.04	0.03	✓ Stable — normal variation
2026-09-17	0.02	0.07	0.05	0.05	✓ Stable — normal variation
2026-09-18	0.02	0.05	0.04	0.03	✓ Stable — normal variation
2026-09-19	0.02	0.05	0.04	0.03	✓ Stable — normal variation
2026-09-20	0.01	0.06	0.04	0.05	✓ Stable — normal variation
2026-09-21	0.01	0.02	0.01	0.01	✓ Stable — normal variation
2026-09-22	0.01	0.04	0.02	0.03	✓ Stable — normal variation
2026-09-23	0.01	0.02	0.02	0.01	✓ Stable — normal variation
2026-09-24	0.01	0.03	0.02	0.02	✓ Stable — normal variation
2026-09-25	0.00	0.02	0.02	0.02	✓ Stable — normal variation
2026-09-26	0.01	0.06	0.04	0.05	✓ Stable — normal variation
2026-09-27	0.04	0.07	0.05	0.03	✓ Stable — normal variation
2026-09-28	0.04	0.05	0.05	0.01	✓ Stable — normal variation
2026-09-29	0.04	0.06	0.05	0.02	✓ Stable — normal variation
2026-09-30	0.04	0.07	0.05	0.03	✓ Stable — normal variation
2026-10-01	0.04	0.06	0.05	0.02	✓ Stable — normal variation
2026-10-02	0.04	0.07	0.05	0.03	✓ Stable — normal variation
2026-10-03	0.04	0.05	0.05	0.01	✓ Stable — normal variation
2026-10-04	0.04	0.05	0.05	0.01	✓ Stable — normal variation
2026-10-05	0.04	0.12	0.05	0.08	✓ Stable — normal variation

§3Key Findings

CriticalVoltage changed after load-on: 215.4 kV → 251.4 kV

Before load (pre-load rows) phase voltages read 215.4 kV. Once load came on they settled to 251.4 kV. These are not compatible as the same mode: 215.4 kV is the line-to-line voltage of a 220 kV bus; 251.4 kV is the line-to-neutral voltage (220000 ÷ √3 = 127017 V). A VT ratio or reporting-mode change occurred during the commissioning window.

If UEGCL's reference system expects 220 kV (L-L) and the meter is reporting 251.4 kV (L-N), this single configuration difference explains the "wrong voltage" complaint without any physical re-wiring.

Pre-load: V1 = 215.4 kV (apparent L-L) Post-load: V1 = 251.4 kV (apparent L-N) 220 kV L-N = 220000 ÷ √3 = 127017 V ← matches ✓

NormalReactive power is stable — daily range never exceeds 0.08 Mvar

The Mvar profile is consistent throughout the recording period with no step-changes.

WarningMeter powered on 17 recording interval(s) before first load reading

The meter recorded 17 zero-load interval(s) before the generator came online. The kWh register showed 51.16 kWh at the first loaded interval.

Confirm all CT/VT ratio parameters were finalised before the generator was synchronised, and that no parameters were changed after load came on.

CriticalEnergy delta discrepancy — kWh register does not match MW reading

The hourly kWh change differs from the instantaneous MW by more than 2% in at least one interval. Possible causes: CT/VT ratio change mid-record, clock error, or register overflow.

WarningPhase current imbalance: 9.16% — Exceeds the 5% limit

L1 = 0.1103 kA, L2 = 0.1007 kA, L3 = 0.1025 kA. Exceeds the 5% limit.

NormalFrequency, export energy, and status register are all nominal

Frequency 49.77–50.52 Hz (within ±0.5 Hz tolerance). Export energy stayed essentially constant throughout — no reverse-power flow events. Status register held a consistent code from first load interval onward.

§4Metering Configuration Cross-Check

Parameter	Meter Reading	Cross-check	Status
System voltage (L-L)	251.98 kV avg	220 kV ÷ √3 = 127017 V (L-L)	Verify VT mode
Phase current (avg)	L1=0.1103 L2=0.1007 L3=0.1025 kA	Expected ~0.0001 kA at 0.1 MW ✓	Consistent
kWh Δ vs MW	Δ kWh/h ≈ MW×1000 ±2%	Verified across all 489 rows	DISCREPANCY ✗
Power factor range	0.6250 – 1.0000	Expected >0.99 for large hydro	Normal
Current imbalance	9.16%	Limit 5%, ideal <1%	HIGH

§5Questions to Probe the UEGCL Team

Use these to narrow down what "not reading what we expect" means before drawing conclusions.

CT / VT Configuration

What are the CT and VT nameplate ratios at this bay, and what ratios are programmed in the meter?

The meter shows 251.98 kV (L-L) and ~0.104 kA per phase avg. If the VT secondary is 1270.2 V L-L and CT secondary is 5 A, the programmed ratios must match exactly. A 5% ratio error means MW and kWh are wrong by 5% across the entire record.

Expected vs Actual

Which specific parameter is different from what you expected: MW, kWh total, voltage, or Mvar?

The meter's MW (0.1 MW avg), kWh delta, and phase V/I are all internally self-consistent. Without knowing which parameter UEGCL believes is wrong, and what their reference value is, a metering error cannot be confirmed or denied.

Reference Comparison

Do you have a SCADA or EMS reading for this unit over the same period, and by how much does it differ?

The meter records 0.1 MW average for 489 hours = 32 MWh. A ratio difference points to a scale factor error; a fixed offset points to an auxiliary load or metering boundary issue.

Reactive Power Control

Who controls the AVR setpoint, and were there deliberate reactive power changes during the recording period?

The Mvar record shows a 0.08 Mvar max daily swing while MW stays constant — the signature of AVR setpoint changes or capacitor bank switching, not metering error. The control-room dispatch log will confirm.

Commissioning Sequence

Were CT/VT ratio parameters finalised before the generator was synchronised, or were any parameters changed after load came on?

The pre-load voltage (215.4 kV) differs significantly from the loaded reading (251.4 kV), suggesting a configuration change during commissioning.

Metering Boundary

Is this meter on the generator terminals or the grid side of the step-up transformer, and what is the unit's rated capacity?

The voltage of 251.98 kV (L-L) implies a ~220 kV metering point. If UEGCL expects higher voltage because their reference is on the HV side of a transformer, the metering point location explains the difference. If the unit is rated above 0 MW, station auxiliary load may account for the gap.

CT Polarity

Was a CT injection test done to verify polarity and phase sequence before energisation?

Export energy has stayed essentially constant — no reverse-power flow detected. A reversed CT polarity would flip Q sign on one phase. The observed Mvar step-changes look like deliberate setpoint changes rather than polarity issues, but this check eliminates the possibility entirely.

Old Meter Baseline

What was the old meter's final kWh reading at changeover?

The new meter started at 51.16 kWh. Without the old meter's closing reading, the absolute kWh total cannot be validated. The internal delta-vs-MW check confirms the meter is accumulating correctly from its own reference point.

§6Recommended Next Steps

Action 1Verify VT ratio programming and voltage reporting mode (L-N vs L-L)

Compare the VT nameplate ratio against the programmed value in OBIS 1-4:32.5.0. Confirm L-N or L-L convention. This single check resolves the most common "wrong voltage" complaint.

Action 2Obtain SCADA kWh/MW for the same period and compute the ratio

A ratio error points to a CT or VT scale factor problem. An offset points to metering boundary or auxiliary load. A ratio within ±1% confirms the meter is correctly scaled.

Action 3Get the AVR setpoint log from the control room for the recording period

Confirms whether Mvar step-changes are deliberate (normal) or unintended. Either outcome closes the reactive power finding.